Aryl halides are extremely less reactive towards nucleophilic substitution reaction because of
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Resonance effect
In a haloarene a lone pair on the halogen is in conjugation with the ring, so by the resonance effect the C–X bond gets partial double bond character and is hard to break.
Three other factors add to it: the carbon of the C–X bond is sp2 hybridised, the phenyl cation that an \(S_N1\) path would need is very unstable, and the electron-rich ring repels an incoming nucleophile.
Why the other options are incorrect
Option (1) Electromeric effect — Incorrect. This is a temporary shift of the \( \pi \) electrons of a multiple bond when a reagent approaches; it does not make the C–X bond stronger.
Option (3) Inductive effect — Incorrect. The −I effect of the halogen makes the attached carbon more positive, which would favour nucleophilic attack, not hinder it.
Option (4) Hyperconjugation effect — Incorrect. This is the delocalisation of \( \sigma \) electrons of C–H bonds next to a \( \pi \) system or a carbocation; it plays no part in the C–X bond of a haloarene.
NCERT (2026-27 edition):
Reactions of Haloarenes – …
